Bridge lan and wifi

You might be referring to using your laptop as a ad-hoc wireless connection host (or atleast i think you are). After setting up the LAN to access the internet, create this ad-hoc connection and then bridge the two connections.

Note: This ad-hoc wireless connect is very temporary, if you restart any machine you will need to manually connect to get a connection. Any device with wifi capability will be able to connect to this ad-hoc connection, rendering the laptop a router-like device.

see here for further information. How to Build a Wireless Network Without Using a Broadband Router | Hardware Secrets